1. Field of the Invention
The present invention relates to a color printer having an apparatus for shifting an ink ribbon. More particularly, it relates to a color printer having an apparatus for swing shifting a ribbon frame on which an ink ribbon cassette is mounted, and simultaneously shifting transversely an ink ribbon in a serial printer, such as a wire dot printer for multi-color printing by means of dots.
2. Description of the Related Art
Recently, multi-color printing has become more and more in demand, and accordingly, a printing system has been developed for color printing with a color ink ribbon having a plurality of color stripes arranged along the transverse direction thereof and which transversely shifts the ribbon.
In such a printing system, the color printer and the shifting apparatus should be small and the shifting operation should be conducted smoothly and precisely.
Japanese Unexamined Patent Publication (kokai) No. 58-12782 discloses a serial-type color printer, in which a ribbon cassette accommodating a color ink ribbon is mounted on a printer base and a ribbon guide is mounted on a carriage so as to be movable up and down to shift the ink ribbon. However, in this printer, the ribbon cassette itself is not swing moved, but remains stationary on the printer base. Therefore, this printer is not appropriate for use with a multi-color ink ribbon having a larger width thereof, since if the ink ribbon was moved or shifted for a long transverse distance, the ink ribbon would be misaligned, which would affect the smooth running of ribbon in the longitudinal direction thereof. In fact, this type of printer is usually used with a two-color ink ribbon, such as a black and red ribbon, having two color-stripes, in which the ink ribbon is shifted along a smaller transverse distance.
Japanese Unexamined Patent Publication (Kokai) No. 59-182773 discloses a color printer, in which an ink ribbon cassette accommodating a color ink ribbon is carried on a carriage which is movable longitudinally along a platen. The ink ribbon cassette is also movable along the platen and swingingly shifted so that a desired color stripe of the ink ribbon is positioned on a predetermined printing line. However, in this printer, the ink ribbon is shifted in unison with the ribbon cassette and there is no ink ribbon guide for guiding the ink ribbon.